OracleFailoverEventArgs Class

The OracleFailoverEventArgs class provides event data for the OracleConnection.Failover event. When database failover occurs, the OracleConnection.Failover event is triggered along with the OracleFailoverEventArgs object that stores the event data.

Class Inheritance

System.Object

System.EventArgs

Oracle.DataAccess.Client.OracleFailoverEventArgs

Declaration

// C#
public sealed class OracleFailoverEventArgs

Requirements

Provider	ODP.NET, Unmanaged Driver
Assembly	`Oracle.DataAccess.dll`
Namespace	`Oracle.DataAccess.Client`
.NET Framework	4.8

Not supported in a .NET stored procedure

Thread Safety

All public static methods are thread-safe, although instance methods do not guarantee thread safety.

Example (Oracle.DataAccess.Client only)

// Transparent Application Failover (TAF) Setup
// Refer Oracle® Database Net Services Administrator's Guide
 
// C#
 
using System;
using System.Threading;
using Oracle.DataAccess.Client;
using Oracle.DataAccess.Types;
 
class FailoverSample
{
  static void Main(string[] args)
  {
    string constr = "User Id=scott;Password=tiger;Data Source=oracle";
    OracleConnection con = new OracleConnection(constr);
    con.Open();
 
    // Register the event handler OnFailover
    con.Failover += new OracleFailoverEventHandler(OnFailover);
 
    Console.WriteLine("Wait for a failover for 5 seconds");
    Thread.Sleep(5000);
 
    con.Close();
    con.Dispose();
  }

  // TAF callback function 
  static FailoverReturnCode OnFailover(object sender, 
    OracleFailoverEventArgs eventArgs)
  {
    switch (eventArgs.FailoverEvent)
    {
      case FailoverEvent.Begin:
      {
        Console.WriteLine("FailoverEvent.Begin - Failover is starting");
        Console.WriteLine("FailoverType = " + eventArgs.FailoverType);
        break;
      }      
      case FailoverEvent.End:
      {
        Console.WriteLine("FailoverEvent.End - Failover was successful");
        break;
      }
      case FailoverEvent.Reauth:
      {
        Console.WriteLine("FailoverEvent.Reauth - User reauthenticated");
        break;
      }
      case FailoverEvent.Error:
      {
        Console.WriteLine("FailoverEvent.Error - Failover was unsuccessful");
 
        // Sleep for 3 sec and Retry
        Thread.Sleep(3000);
        return FailoverReturnCode.Retry;
      }
      case FailoverEvent.Abort:
      {
        Console.WriteLine("FailoverEvent.Abort - Failover was unsuccessful");
        break;
      }
      default:
      {
        Console.WriteLine("Invalid FailoverEvent : " + eventArgs.FailoverEvent);
        break;
      }
    }
    return FailoverReturnCode.Success;
  }
}